Connector for flexible flat strip cables

ABSTRACT

The present invention relates to a connector ( 1 ) for flat flex cables ( 2 ), with a housing ( 3 ), in which is provided: at least one introduction opening ( 4 ) for one end of a flat flex cable, spring contacts ( 5 ) for connecting the at least one flat flex cable ( 2 ) with contacts ( 6 ) or with another flat flex cable ( 7 ) and at least one strain relief ( 8 ). The strain relief ( 8 ) has a slide ( 9 ), which is introduced into the introduction opening ( 4 ) above the flat flex cable ( 2 ), the flat flex cable ( 2 ) being bent by a rib ( 10 ) on slide ( 9 ) into a recess ( 11 ) in the bottom of introduction opening ( 4 ) until the slide ( 9 ) locks into its final position on housing ( 3 ).

The present invention concerns connectors for flat flex cables accordingto the preamble of patent claim 1.

Such a connector is known, for example, from GB-1,317,264 B1. Theconnector described therein has, in a housing, spring contacts which arepressed against regions of the flat flex cable that are stripped ofinsulation, while the opposite-lying ends of these spring contacts arein the shape of female connectors for the uptake of male connectors. Theconnection of two flat flex cables with one another is carried out bydirect contact of the parts of the flat flex cable that are stripped ofinsulation. The overall structure of the connector described therein hasproven to be complicated with respect to its handling and an effectivestrain relief cannot be recognized.

The object of the present invention is to extensively improve aconnector of this type such that its handling is simplified and a securestrain relief is continually assured in the case of the flat flex cablesthat participate in it.

This object is solved according to the claims.

Features of preferred embodiments of the present invention arecharacterized in the subclaims. The concept of the invention is based onthe following: when the connector is introduced into its final position,the one or more flat flex cables that participate in it are clamped intoa “baffle plate”, in which the cables are very sharply bent locally, sothat the adhesion friction forces that occur in the strain loading areso great that a tearing out of the flat flex cable from the connectorcan be effectively prevented. The operator who assembles the connectorrecognizes the obtaining of the final position by the “clicking in” ofthe connector elements.

In the following, the invention will be explained in more detail basedon the description of three embodiments of the present invention withreference to the drawing. The following are shown therein:

FIG. 1 shows a perspective view, which is partially cut away, of a firstembodiment of the connector according to the invention;

FIG. 2 shows the connector according to FIG. 1 in the pre-lockingposition and in the final position;

FIG. 3 shows another embodiment of the present invention in thepre-locking position and in the final locked position; and

FIG. 4 shows a third embodiment of a connector according to the presentinvention in perspective view, which is partially cut away, in thepre-locking position and in the final locked position.

The connector 1 shown in FIG. 1 has a housing 3, with an introductionopening 4 for a flat flex cable 2. The latter is inserted into theintroduction opening 4 until it strikes the end of the opening. At itshead end, the flat flex cable 2 has conductive tracks stripped ofinsulation, onto which press the spring contacts 5. In addition to theflat flex cable 2, a slide 9, which has several functions, is introducedinto the introduction opening 4. First of all, it effects a strainrelief of the flat flex cable 2, which is described in more detailbelow, and secondly, it presses the spring contacts 5 more strongly ontothe conductive tracks of the flat flex cable 2, which are stripped ofinsulation. The strain relief is effected by a ramp 12 at the back endof the slide, viewed in the insertion direction, which, with its backend, projects up over the introduction opening 4, when it is in theposition prior to assembly. On its bottom side, ramp 12 has a rib 10running crosswise to the insertion direction. In the final lockedposition, this rib 10 lies opposite a recess 11 or a passage 11 in thebottom of housing 3. In addition, the slide 9 has on its end anoperating surface 14 with a gap, through which the flat flex cable 2 isconducted. The operating surface 14 serves as the surface for anoperator to introduce force by pressing on the operating surface in theinsertion direction, until the slide 9 locks into its final position. Onthe way to this final position, ramp 12 is pressed downward through theupper edge of the introduction opening 4, so that the cross-rib 10presses the flat flex cable 2 into the recess or into the passage 11.The pre-locking position and the final position are shown in FIG. 2. Itcan be clearly recognized in FIG. 2 b that the cross rib 10, in itsfinal position, comes to lie tightly at the front edge of the recess oropening 11, viewed in the insertion direction, so that the flat flexcable 2 experiences an almost 90-degree bend, which represents aneffective strain relief.

In final position, the upper back edge of the slide 9 locks under ashoulder 15, which is provided in the operating surface 14.

In the region of its head end, slide 9 also has an additional two ramps9 a, which, when slide 9 is inserted into the introduction opening 4,press the legs 5 a situated at the ends of pressure springs 5 locatedaway from flat flex cable 2 and press the entire essentially U-shapedspring contacts 5 in the direction onto the flat flex cable 2. In thisway, a more stable and more secure electrical contact is assured betweenthe contact springs 5 and the conductive tracks of the flat flex cable2, which are stripped of insulation.

In the embodiments shown in FIGS. 1 and 2, the spring contacts 5 havecontact sockets 16 at their sides that are not in contact with the flatflex cable 2, which are arrested in corresponding openings in thehousing 3, for contacting the flat flex cable 2 with male connectors ofa complementary connector.

FIG. 3 shows an embodiment of a connector according to the invention,with which two flat flex cables 2, 7 can be connected with one another.FIG. 3 shows the pre-locking position (upper left) and the final lockedposition (lower right). As can be readily seen, the structure of thisconnector differs from that shown in FIGS. 1 and 2 only by the fact thata mirror-symmetric doubling has occurred, with two anti-parallelintroduction openings 4, 4′ in a housing 3 and with spring contacts 5,5′, whose back ends are joined together, or which are made up in onepiece from the outset. The strain relief function and the pressing ofspring contacts 5, 5′ onto the parts of flat flex cables 2, 7 which arestripped of insulation are described identically to those with referenceto FIGS. 1 and 2. The spring contacts 5, 5′ in this embodiment arefastened by means of an arresting part 2* that can be introducedcrosswise to the insertion direction on housing 3 in a way known in andof itself. That is, there results a fixing of position in the lockedfinal position of fastening part 20 in housing 3.sic; 20?—Trans. Note.

FIG. 4 shows a third embodiment of a connector according to theinvention, in which two flat flex cables 2, 7 can be inserted intointroduction opening 4 and push onto two rows of spring contacts 5, 5′which are disposed in a mirror-symmetric manner and each of which isformed in just the same way as in the first embodiment. In distinctionto the first embodiment, here the two flat flex cables 2, 7 are guidedby means of an intermediate member 17 and a slide 18 connecting theretoand fastened. On its head end, the intermediate member 17 has shoulders,with which the legs 5 b of the spring contacts which are adjacent to theconductive tracks are pressed onto the conductive tracks. Theintermediate member 17 is slotted on its back end along a central planeparallel to the extension of the flat cable. The wedge-shaped tip ofslider 18 engages in this slot, so that the back end of the intermediatemember 17 is propped open and thus the flat flex cables 2, 7 pressagainst the inner walls of the introduction opening 4.

Here, at the back ends of the slotted parts of the intermediate member,strain relief projections 20 are provided, which engage in correspondingopenings 21, which are punched at the appropriate distance in the sidesof the flat flex cables. The projections thus pass through the openingsin flat flex cables 2, 7 and enter cross slots 22, which are alsoincorporated at this level in housing 3. The slide 18 is locked in itsfinal position on housing 3 in a way known in and of itself, so thatboth a high pressing force of the contact springs as well as a securestrain relief are assured.

In the example of embodiment shown in FIG. 4, contact sockets are alsoformed at the other ends on spring contacts 5. This is not to beunderstood as limiting, however; contact pins or even contact springsfor connecting several flat flex cables 2, 7, as in the second exampleof embodiment, could just as well be arranged.

The three embodiment examples explained above show the broad field ofapplication of the present invention, wherein the description of theembodiment examples also only serves for purposes of illustration and isnot to be construed as limiting.

1. A connector for flat flex cables with a housing, in which is providedat least one introduction opening for a flat flex cable end, springcontacts for connecting the at least one flat flex cable with contactsor another flat flex cable and at least one strain relief, is herebycharacterized in that the strain relief has a slide, which is introducedinto the introduction opening over the flat flex cable, wherein the flatflex cable is bent by a rib on slide into a recess at the bottom of theintroduction opening until the slide locks in its final position onhousing.
 2. The connector according to claim 1, further characterized inthat the slide, proceeding backward from its tip, forms a ramp, whoseback end projects above the level of the opening during introductioninto the opening and slides on the upper edge of the opening of theintroduction opening, whereby the rib is pressed into the recess.
 3. Theconnector according to claim 1, further characterized in that the slidehas, on its back end, an operating surface for pressing it in, at theupper edge of which is disposed a shoulder for the locking of ramp. 4.The connector according to claim 1, further characterized in that thespring contacts at the head end of the introduction opening prestressedperpendicular to its longitudinal axis press on regions of theconductive tracks of the flat flex cable that are stripped ofinsulation.
 5. The connector according to claim 4, further characterizedin that the spring contacts are essentially bent in U-shape and theirlegs located away from the flat flex cable are pressed onto the flatflex cable by two ramps on slide.
 6. The connector according to claim 4,further characterized in that the spring contacts are formed on theirends pointing away from the introduction opening as female connectors orplug contacts.
 7. The connector according to claim 4, furthercharacterized in that the spring contacts are bent in U-shape at both oftheir ends and two introduction openings are disposed with their headends abutting one another in housing for connecting two flat flexcables.
 8. The connector according to claim 1, further characterized inthat the introduction opening takes up two flat flex cables, and tworows of spring contacts are provided one above the other.
 9. Theconnector according to claim 8, further characterized in that the springcontacts are held by an intermediate member in the introduction opening,and this member can be moved to the head end of the introduction openingby a slider and can be propped open at its back ends, in order to pressstrain relief projections disposed therein into corresponding openingspunched in the flat flex cables.
 10. The connector according to claim 9,further characterized in that at the level of openings in the flat flexcables, housing has slots, into which the strain relief projections ofintermediate member can be moved.
 11. The connector according to claim8, further characterized in that the spring contacts are bent convexlyat their legs that can be pressed onto flat flex cables and are pressedby shoulders of intermediate member onto the flat flex cables.
 12. Theconnector according to claim 11, further characterized in that on itshead end, the intermediate member has ramps, with which the legs ofspring contacts located away from the flat flex cables are to be pressedonto the flat flex cables.
 13. The connector according to claim 8,further characterized in that the slide can be locked in its finalposition on housing.